JACKETED GASKET
A Jacketed gasket features an inner soft material core and an outer metallic shell. The inner filler material provides resilience to the gasket, whereas the metal jacket protects the inner core of the gasket and withstands the pressure, the temperature, and the corrosion of the process.
Metal jacket gaskets are available with a single or double jacket and are widely used for pumps, valves, pressure vessels, and other mechanical equipment.
A metal jacket gasket requires flat face flanges with a smooth face finish to seal effectively.
The size range and thickness tolerances for this type of gaskets are covered by ASME B16.21 specification:
OD: Less than 5,000mm
Thickness: 2~8mm with tolerance +0.03 inch. to -0.000 inch (+0.8mm, -0.0mm)
JACKETED GASKET MATERIALS
Metal Jacket Materials
The table shows the most common metals used for jacketed gaskets and the recommended temperature range:
| Jacket Materials | Hardness HB | Temp.℃ |
| Carbon Steel | 90 | -60~+450 |
| 304 (L) | 130 | -270~+550 |
| 316 (L) | 130 | -270~+550 |
| 321 | 130 | -270~+550 |
| Monel | 110 | -60~+500 |
| Inconel | 90 | -60~+600 |
| AL | 30 | -250~+300 |
| CU | 80 | -250~+400 |
Inner Core Materials
Metal jacket gaskets have a soft inner core, which may be manufactured in materials as:
Non-Asbestos millboard and other non-asbestos materials (aramid, glass fiber, inorganic fibers, etc)
CAF
Rubber
PTFE
Graphite
JACKETED GASKET TYPES
The two main types of metal jacketed gasket are the single and the double jacket designs. Besides these two basic types, other designs are available on the market as illustrated below:
 | Double Jacketed Corrugated
— soft filler
Reduced contact area, enhances compression characteristics, suitable for uneven flanges. |  | Double Jacketed Corrugated
— metal filler
Usually stainless outer casing with soft iron filler ring.
Core material available St. St. -304.316L.321
Soft iron, Monel, Inconel |  | Single Corrugated
— asbestos rope filler
Typically used on very poor or pitted flanges, low bolt loading requirement. |  | Metal Jacket Laminates
— soft filler
Combines flexible graphite with stainless steel core material |  | Solid metal ring machined on each contact face to provide a serrated surface finish covered with Graphite.
PTFE Nonas or Asbestos. |
|  | Double Jacketed – soft filler
Used on high-temperature pressure applications or where corrosion problems may exist |  | Single Jacketed – metal filler
– partly enclosed
Very seldom used, old design. Used in applications where poor or pitted flanges exist on one facing. |  | Single Jacketed – Soft filler
– partly enclosed
Used on narrow flanges |  | Single Jacketed – Soft filler
– open outside edge
Used in narrow flanges, protection of filler cleared for by casing |  | Single Corrugated – no filler
Used mainly in valve applications, small recess gap. Sometimes referred to as Taylor ring. |
|
JACKETED GASKET DIMENSIONS
Class 150-400
| NPS | d1 | d2 |
| 150 | 300 | 400 |
| 1/2 | 23.8 | 44.5 | 50.8 | 50.8 |
| 3/4 | 31.8 | 54 | 63.5 | 63.5 |
| 1 | 36.5 | 63.5 | 69.9 | 69.9 |
| 1¼ | 46 | 73 | 79.4 | 79.4 |
| 1½ | 52.4 | 82.6 | 92.1 | 92.1 |
| 2 | 73.2 | 101.6 | 108 | 108 |
| 2½ | 85.9 | 120.6 | 127 | 127 |
| 3 | 107.8 | 133.4 | 146.1 | 146.1 |
| 4 | 131.8 | 171.5 | 177.8 | 174.7 |
| 5 | 152.4 | 193.8 | 212.8 | 209.5 |
| 6 | 190.5 | 219.1 | 247.7 | 244.5 |
| 8 | 238.3 | 276.3 | 304.8 | 301.7 |
| 10 | 285.8 | 336.6 | 358.8 | 355.6 |
| 12 | 342.9 | 406.4 | 419.1 | 415.9 |
| 14 | 374.7 | 447.7 | 482.6 | 479.5 |
| 16 | 425.5 | 511.2 | 536.6 | 533.4 |
| 18 | 489 | 546.1 | 593.7 | 590.6 |
| 20 | 533.4 | 603.3 | 650.9 | 644.5 |
| 24 | 641.4 | 714.4 | 771.6 | 765.3 |
| NPS | d1 | 150 | 300 | 400 |
Class 600-2500
Jacketed gasket dimensions for AMSE B16.5 flanges
| NPS | d1 | d2 |
| 600 | 900 | 1500 | 2500 |
| 1/2 | 23.8 | 50.8 | 60.4 | 60.4 | 66.8 |
| 3/4 | 31.8 | 63.5 | 66.7 | 66.7 | 73.1 |
| 1 | 36.5 | 69.9 | 76.2 | 76.2 | 82.5 |
| 1¼ | 46 | 79.4 | 85.8 | 85.8 | 101.6 |
| 1½ | 52.4 | 92.1 | 95.3 | 95.3 | 114.3 |
| 2 | 73.2 | 108 | 139.7 | 139.7 | 143 |
| 2½ | 85.9 | 127 | 161.9 | 161.9 | 165.1 |
| 3 | 107.8 | 146.1 | 165.1 | 171.5 | 193.8 |
| 4 | 131.8 | 190.5 | 203.2 | 206.5 | 231.9 |
| 5 | 152.4 | 238.2 | 244.6 | 250.9 | 276.3 |
| 6 | 190.5 | 263.6 | 285.8 | 279.4 | 314.5 |
| 8 | 238.3 | 317.5 | 355.6 | 349.3 | 384.3 |
| 10 | 285.8 | 396.9 | 431.8 | 431.8 | 473.2 |
| 12 | 342.9 | 454.1 | 495.3 | 517.6 | 546.1 |
| 14 | 374.7 | 489 | 517.6 | 574.7 | … |
| 16 | 425.5 | 562 | 571.5 | 638.2 | … |
| 18 | 489 | 609.6 | 635 | 701.8 | … |
| 20 | 533.4 | 679.5 | 695.5 | 752.5 | … |
| 24 | 641.4 | 787.4 | 835.1 | 898.6 | … |
Metal Jacketed Gasket
Schedule of Standard Shapes for Heat Exchanger Gaskets
